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An operating temperature is the allowable temperature range of the local ambient environment at which an electrical or mechanical device operates. The device will operate effectively within a specified temperature range which varies based on the device function and application context, and ranges from the minimum operating temperature to the maximum operating temperature (or peak operating ...
A Carnot cycle is an ideal thermodynamic cycle proposed by French physicist Sadi Carnot in 1824 and expanded upon by others in the 1830s and 1840s. By Carnot's theorem, it provides an upper limit on the efficiency of any classical thermodynamic engine during the conversion of heat into work, or conversely, the efficiency of a refrigeration system in creating a temperature difference through ...
The efficiency of an engine is defined as ratio of the useful work done to the heat provided. where, is the heat absorbed and is the work done. Please note that the term work done relates to the power delivered at the clutch or at the driveshaft . This means the friction and other losses are subtracted from the work done by thermodynamic expansion.
A nickel–metal hydride battery ( NiMH or Ni–MH) is a type of rechargeable battery. The chemical reaction at the positive electrode is similar to that of the nickel-cadmium cell (NiCd), with both using nickel oxide hydroxide (NiOOH). However, the negative electrodes use a hydrogen-absorbing alloy instead of cadmium.
The engine temperature on modern cars is primarily controlled by a wax-pellet type of thermostat, a valve that opens once the engine has reached its optimum operating temperature. When the engine is cold, the thermostat is closed except for a small bypass flow so that the thermostat experiences changes to the coolant temperature as the engine ...
The black-line diagram represent a jet engine cycle with maximum pressure p2 and temperature T3. When component inefficiencies are incorporated for a real engine the blue-lined area is the result which shows that entropy is increased in each process, including the combustion pressure loss from p3 tp p3', by the loss-making characteristics of ...
The thermal efficiency of a heat engine is the percentage of heat energy that is transformed into work. Thermal efficiency is defined as. The efficiency of even the best heat engines is low; usually below 50% and often far below. So the energy lost to the environment by heat engines is a major waste of energy resources.
The Carnot engine is the most efficient heat engine which is theoretically possible. [ 3] The efficiency depends only upon the absolute temperatures of the hot and cold heat reservoirs between which it operates. A heat engine acts by transferring energy from a warm region to a cool region of space and, in the process, converting some of that ...